I too lost sensitivity in my skin. It’s also ashy and chronically dry. Whenever I shave, it’s like a mild dermabrasion, so I have to do so only every 3 or 4 days, and use a Bump-Fighter razor. Then, when the facial hair starts to grow back, I can feel it stinging for about 24 hours – and the hair itself feels like a wire brush. My lips as well have been damaged, like the normal healthy outer layer of skin just disappeared.
The amount of sensitivity loss varies around my body. The tips of my fingers are the worst, with about 40% loss, with all other areas being someone less. My skin also feels waxy in places, kind of like a wet suit, rather than naturally-oiled leather (i.e., healthy skin).
A lot of this happened after I went off Propecia. Dermatologist have no idea what to do.
I can only hope that when therapies for PFS are developed, they will help such skin issues as well.
What I always found odd is that, aside from my skin problems, I have no other PFS symptoms. I guess I should count myself lucky, if profoundly uncomfortable at times.